It could very well be a Tempo (I'm on the hopeful side). The white seat tube, with the Schwinn logo in that color and the Columbus Tenax sticker at the bottom are all look/color correct for that model in that year. All the parts on it look more or less correct to the year, if not specific model. 105, Suntour Sprint with Accushift it seems... it may be a bit of a Frankenbike, but they're all good components. I'd see if you can talk him down significantly, provided it fits, that's the most important thing. Like J.Oxley said, the market for bikes this size is a lot smaller which is probably why it's been up for sale for the last 22 days.

As for it not being a Tempo I look at it this way... why on earth would someone go out of their way to fake a Tempo??